The United Mine Workers Union suggests election year politics may be the reason.

NPR, the Center for Public Integrity (CPI) and the Gazette collaborated on a series of reports in July that showed a 40-year effort to control coal dust and stem the miners' disease known as black lung was plagued by weak enforcement by government regulators and inaccurate and falsified coal dust measurements by industry.

More than 70,000 coal miners have died from black lung since a law combating the disease was passed in 1969. About 10,000 have died in the last 20 years and data gathered by the National Institute of Occupational Safety and Health (NIOSH) indicate the disease is on the rise and is striking younger miners.

Gazette reporter Ken Ward, who has focused on coal industry issues for two decades, reports that "government records indicate that the black lung rule has not yet reached the White House Office of Management and Budget, which must review it before a final version can be issued."

The Mine Safety and Health Administration has proposed cutting in half miners' exposure to coal dust underground and spent two years developing a rule to impose those limits. Congressional Republicans stalled the measure in a budget bill and required a Government Accountability Office (GAO) review of NIOSH studies showing a rise in black lung.

The GAO report came out two months ago and it backed the NIOSH data. That cleared the way for action on the MSHA rule.

As the Gazette reports, federal mine safety chief Joe Main told the United Mine Workers Journal this week that, "We have finalized our work here. ... It's moving through the next level, but that does take some time."

Ward asked Main to be specific about the proposal during a visit to Charleston this week. "It's going through the process," Main told Ward. "It's still in the process." He declined to provide details.

Ward asked United Mine Workers (UMWA) spokesman Phil Smith for comment and Smith raised the possibility of election year sensitivity given Republican attacks in the battleground states of Ohio and Virginia accusing President Obama of waging a "war on coal."

"If they're worried about Republicans calling this another job-killing regulation," Smith told the Gazette, "let's remember that coal miners are still dying from black lung."

The UMWA, with Main as its safety chief, actually opposed new coal dust regulations in the past, saying they didn't go far enough. The union also objected to elements of MSHA's current proposal. But Smith said "We would hope that the rule would be put in place and enforced as soon as possible."

Industry groups have also opposed elements of the proposed regulations, arguing that the MSHA approach is too broad and fails to specifically target the coal mines and coal seams in portions of Appalachia where the black lung increase is most pronounced.

Clarification, Oct. 13, 2012, 12:34 E.T.:

Phil Smith of the United Mine Workers union did not make an election year connection to the black lung issue in his comment to the Charleston Gazette. And he did not intend for his comment to be interpreted as making an election year connection to the issue. Smith tells NPR in response to this post that he and UMWA president Cecil Roberts have spoken about "the GOP's continual opposition to new regulations on coal dust" for more than a year.